Overall Advantages Of Aftermarket Rb25 Inlet Manifold ?

[GTSBoy]

Well, the Neo plenum is a different shape. You can bet your last $ that the Nissan boys tweaked the internal shapes to suit what else they were doing with the changes to the Neo head. But it will be broadly similar to the other RB25s. There's only so much you can do with that layout.

I think the money and time spent making a Neo's plenum fit an earlier RB25 would return better results spent on fixing something else up.

[discopotato03]

Well with a little luck it'd be a cheaper option provided it bolted to the head the same . Are the plenum ports and bolt patterns the same as R33 ?

I did read somewhere that the lower section has longer runners so they obviously changed a few things as part of a package .

If a complete Neo engine fits in an R33 bay then this manifold must be usable .

A .

[GTSBoy]

I know of at least 1 Neo that has R33 inlet manifold on it, so the opposite must be possible. But I must stress what I wrote above. I don't think the effort and expense involved in swapping a Neo manifold onto an older engine would provide equivalent benefits. Spend the same time and money elsewhere, where it is known to offer worthwhile results.

[75coupe]

Or get a ff plenum and be one of the cool kids

[discopotato03]

Well if the factory one does a better job than some and only slightly worse than the best then it looks pretty good cost and effort wise .

Hard to fathom how the single throttle on the side of the plenum does it .

I did see a pic of two throttles on a standard plenum but not sure if that was photoshop job.

A .

[KiwiRS4T]

Well if the factory one does a better job than some and only slightly worse than the best then it looks pretty good cost and effort wise .

Hard to fathom how the single throttle on the side of the plenum does it .

I did see a pic of two throttles on a standard plenum but not sure if that was photoshop job.

A .

The Neo DE engine has a remote throttle feeding two pipes to the plenum - might be what you saw?

[GTSBoy]

Yuh, that's a point of commonality between the (much newer) Neo DE, and the (far older) Toyota 7M.

[Dan_J]

Yes, that was a plazmaman item. By doing so he's also shortened his cooler piping, that could possibly be the response gain.

seems running the stock bottom half with custom bolt on top part may gain more results compared to the custom shorter runners in one piece.

one main benefit from going to FF is for shorter piping meaning more response, no point running one if its gonna be laggy

[discopotato03]

No the pic I saw had two throttlebodies bolted to the cam cover side of the plenum chamber .

The Neo DE idea looks good but they didn't do it with the Neo turbo variant and there must have been a good reason for that .

A .

[GTSBoy]

Lack of room was the reason. Traction control throttlebody would have been hanging out over the turbo.

[WMDC35]

i've seen that twin throttle body on the stock plenum too, think its on a 30de in the na thread

[BLITZ-26]

i just cut and modifyed the stock manifold mounted the throttle body on the front ... all the same as a stocker with the benifits of a ffp heaps of ppl have said it upseats things but mate has his 360kw rb25 running it and no problems at all once its all shaved back u would think it was factory

[ahhbee]

the argument with doing that was always that nissan design it for a side throttle body and had flow characteristics to the cyclinders as such. moving the throttle body to the front is mean to lean out the rear cylinders, now ive never had a good look at the shape inside the top half of the plenum but it wouldn't surprise me if the top half of the runners are specifically shaped based upon the side throttle body. in which case moving it to the front is like loading a gun for russian roulette, never know if or when it'll go bang. im not saying that it may not have worked for your mate, simply that its not ideal and if for some reason your desperate to go ffp you are better off using one that was designed as a ffp front the start.